Method of drilling hinge pin holes in shoe lasts



Sept 1' 1940. J. M. MADIGAN METHOD OF DRILLING HINGE PIN HOLES IN SHOELASTS Filed Oct. 21, 19;? 3 t -Sheet l igl n o H fl w/ e g v mMM M] UMIn 0 b &

Sept. 17, 1 940. J,M M D N 2,214,837

METHOD OF DRILLING HINGE PIN HoLris IN SHOEILAS'IS 3 Sheets-Sheet 2Filed Oct. 21. 1937 lnven'for.

\John I LMudigun WMzW ATTys.

Sept. 17, 1940.

J. M. MADIGAN METHOD OF DRILLING HINGE PIN HOLES IN SHOE LAS'I'S 3Sheets-Sheet 3 Filed Oct. 21. 1931 -M. Luflili Q r lnvenTof:

v igan AT Tys.

1 i QR mm Patented Sept. 17, 1940 PATENT OFFICE METHOD OF DRILLING HINGEPIN HOLES 1N SHOE LASTS mm M. Madigan, Haverhill, Mass.

Application October 21, 1937, Serial No. 170,209

1 Claim.

This invention relates to methods and apparatus for drilling parallelhinge pin holes for twopart lasts.

In usual last constructions the pin holes for the hinge pins are boredfrom one side of the last entirely through to the other side. Inperforming such drilling operations some times a single drill is usedand in others two or more drills are employed, the last usually beingpositioned by hand relatively to the drill or drills or adjustablypositioned by hand in a jig. The object of the present invention is toeliminate all guess work of free-hand positioning of the last to bebored, second to prevent diversion of the drill from its proper path byuneven resistance to penetration of the drill caused by differentconditions inherent in the wood of the last, such as differences in thegrain of the wood, as for example, where a portion of the last to bedrilled is of a plain grain maple, while other portions are of theso-called curly maple which is much more dimcult of penetration with thegrain so running as to tend to divert the direction of the drill.

In the usual drilling of lasts one or both of the hinge pin holes isfrequently diverted from its proper position so that it is in angularrelation to the other. Under such circumstances when the last is cutinto two sections and the hinge introduced there will be a binding atone side of the cut and a separation at the other side, therebydistorting the last and also interfering with the proper manipulation ofthe last.

One of the objects of the present invention is to obviate this defect inlast manufacture and to insure perfect registration when assemblin thefore part to the heel part of the last by insertion of the connectingmechanism.

The present invention comprises novel steps in the method of makingtwo-part lasts which will insure proper parallelism of the hinge pins.

One of the steps in the method comprises drilling coaxially alined holesfor the respective hinge pins from predetermined points on oppositesides of the last, thereby insuringaccuracy of parallelism of the hingepins when the parts of the last are assembled and secured together bysuitable hinges. v

Another step in the method consists in terminating the axially alinedbores for the hinge pins short of communication with each other andremoving the web of material between the adjacent ends of the bore byrouting out the recess which receives the hinge.

The method also comprises simultaneously drilling portions of both hingepin bores from opposite sides of the last in such manner that theopposite axially alined bores will be simultaneously produced, therebyenabling a more rapid manufacture of the device than has heretofore beenaccomplished.

By thus applying the pressure of the boring mechanisms simultaneously toboth sides of the last the likelihood of displacement of the last fromits support, which is inherent in boring the last from one side, iseliminated. Furthermore, by the present method the depth to.which eachdrill must penetrate is considerably shorter than when the last isdrilled clear through so that there is less likelihood of flexure of thedrill particularly if it encounters relatively harder portions of thewood.

While the steps of the method of the present invention may be performedmanually with usual last-clamping and drilling mechanisms, desirably themethod is performed by a suitable machine illustrative types of whichare shown in the accompanying drawings, in which,

Fig. 1 is a plan view of a last-boring machine illustrating the mannerin which the hinge pin holes are bored in the last;

Fig. 2 is a detail side elevation of the portion of the machine whichsupports the last in proper adjustment to templets for simultaneouslyguiding the pairs of drills for boring the hinge pin holes;

Fig. 3 is a vertical transverse sectional view on lines 3-3 Fig. 2;

Fig. 4 is a vertical transverse sectional view on lines 4-4 Fig. 2;

Fig. 5 is a detail transverse sectional view on the broken line 5-5 Fig.2;

Fig. 6 is a side elevation of a modified form of construction forclamping the last and for guiding the drills properly to produce axiallyalined hinge pin holes;

Fig. 7 is a vertical transverse sectional view on lines 1'| Fig. 6; and,

Fig. 8 is a detail plan view of the adjustable mechanism shown in Fig. 6for supporting and clamping the toe portion of the last in properposition for boring the parallel holes for the two parallel drills ofone drilling mechanism in axial alinement with complementary drills ofthe other drilling mechanism.

The drilling mechanism is conventionally shown and is of course mountedupon a suitable bed plate. Any suitable drilling mechanism may beemployed. As conventionally illustrated herein the drilling mechanismcomprises two casings I and 2 which are suitably mounted upon a bedplate (not shown) and containing suitable mechanism for driving andfeeding pairs of drills 3 and 4 and 5 and 6 respectively. Suitableshafts I and 9 for actuating the driving mechanism may be driven by anelectric motor or from any other usual source of power.

The mechanism for supporting the last as illustrated in Figs. 1 to 5inclusive comprises a base 9, preferably of rectangularform, havingintegral therewith or secured thereto intermediate of its ends similarvertical templets III and I I provided respectively with pairs of holesI2 and I3 adapted respectively to guide the pair of drills 3 and 4 andthe pair of drills 5 and 8 in such manner as accurately to aline thedrill 3 with the complementary drill 5 and the drill 4 with thecomplementary drill 6.

Suitable means are provided for supporting and clamping the last in suchposition as to permit the drilling of the hinge pin holes in proper relation to the lines upon which the last is to be severed to provide atwo-part hinge last. The last I 4, which usually is made of maple wood,and may be of any suitable configuration and size, is bored to providethe hinge pin holes before the last is cut to permit pivotal movementbetween the heel and toe portion. The heel portion of the last isprovided with the usual socket containing a thimble I5 to receive thejack pin of the lasting machine.

In the construction, as shown in Figs. 1, 2, and

3, the heel portion of the last is supported upon an adjustable pin I6which fits within the thimble I5 and is pivoted at its lower end upon apin H which is mounted in bosses I8 and I9 extending upwardly from theplate 29 which is desirably countersunk into the base 9 and securedthereto by suitable machine screws. The boss I9 preferably extendsupwardly a considerable distance above the base and in engagement withthe, pin I6 and is provided adjacent its upper end with an arcuate slot2| concentric with the axis of the pin H. A stud 22, which is fixedlysecured to the pin I6, extends through the slot and is provided with ascrewed end portion which is engaged by a milled nut 23 adapted whentightened up adjustably to clamp the pin I6 firmly against the boss I9.By reason of this construction longitudinal adjustment of the heelportionof the last is permitted properly to position the last relativelyto the drills for boring the hinge holes in the last.

Means for supporting the toe portion of the last preferably include asupporting member of flat sheet steel having end portions 24 and 25welded or otherwise secured to the inner face of the templets I0 and IIand having a central downwardly extending V-shaped portion 26 which isprovided with a removable resilient lining 21 of rubber, or othersuitable material, which is adapted to be replaced for different sizesand contours of the arch portion of the last.

Suitable means are provided for adjustably supporting the toe portion ofthe last operable in conjunction with the heel support above describedto position the last accurately relatively to the axes of the drills. Inthe preferred construction illustrated a vertical cylindrical stand 28is rigidly mounted in the base 9 and receives the cylindrical lower endof a rod 29, which has an upper screw threaded portion. The upper end ofthe rod is provided with an enlarged head 30 to engage and support thetoe portion of the last. The cylindrical stand 28 is provided with avertical slot which forms a guide for a pin 3I which is mounted in thecylindrical rod 29 and prevents rotation of the rod. A knurled nut 32,which engages the screw threaded portion of the rod 29 and is seatedupon the upper end of the cylindrical stand 28, provides means foradjustably raising and lowering the rod and the head thereof whichsupports the toe portion of the shoe.

Suitable means are provided for clamping the sides of the toe portion ofthe last: As illustrated in Figs. 2 and 5 the cylindrical stand 28 isprovided with a rearwardly extending boss 33 having a vertical slot 34in which is seated the cylindrical portion 35 of a rod having screwthreaded portions 36 and 31 of opposite pitch and provided with asuitable knurled head 38 for conveniently rotating it. Clamping jaws 39and 40 to engage the side portions of the last are provided with offsetlower end portions which engage respectively the screw threads 36 and 31of the rod 35. The lower ends of the clamping members desirably are flatand engage the upper face of the base 9. When the toe portion of thelast has been properly positioned by adjustment of the supporting rod29, the rod 35 may be rotated by its knurled head 38 firmly to clamp thejaws 39 and 40 against the sides of the last.

In order to aid in positioning the last properly and to prevent possiblelongitudinal movement thereof during the drilling operation, an abuttingmember is provided to engage the rear end of the heel portion of thelast. In the construction illustrated in Figs. 1 and 2 the abuttingmember is in the form of a casting having a vertical stand 4| having arearwardly curved upper end and a reenforcing web 42 which is formedintegral with a slide 43 which is mounted in suitable ways 44 in thebase 9 and is normally forced toward the heel by springs 45 interposedbetween the slide and a plate 46 which is welded to or otherwise securedto the end of the base.

In the operation of the machine above described the heel portion of thelast is placed upon the pin I6 and forced downwardly until the upper endof the pin engages the base of the thimble l5. As it is thus forceddownwardly the abutting member 4| is forced rearwardly against thepressure of the springs 45 and the arch portion .of the last caused toengage the resilient lining 21 of the arch-supporting member, it beingunderstood that the resilient member 2'! is detachable so that suitableshapes may be provided for lasts of different sizes and of diiferentcontour. The last is then adjusted longitudinally properly to positionit with respect to the drills and locked in adjusted position by settingup the nut 23 which clamps the pin upon the boss I9. The toe portion ofthe last is then positioned by vertical adjustment of the supporting rod29 and head 30 to position the last vertically relatively to the axes ofthe complementary drills. The knurled head 38 of the rod 35 is thenrotated to cause the clamping jaws 39 and 40 firmly to engage the sidesof the toe portion of the last. When the last is thus properlypositioned with respect to the guides I2 and I3 of the respectivetemplets, the drills are actuated to bore the hinge pin holessimultaneously from both sides of the last, thereby subjecting the lastto equal pressure upon both sides which will prevent the like-' movedfrom the clamping support and the toe v and heel portion severed bysawing a cut 48 substantially vertically from the arch portion of thesole of the last a predetermined distance, then by sawing a cylindricalcurved cut 49 having an axis 58 which is located in the last above theplane of the axes of the hinge pin holes. The upper portion of the lastis then sawed in converging planes 5| and 52 from the heel and archportions of the last respectively to the circular cut 49, therebysevering the toe portion of the last from the heel portion in such amanner that when the last is assembled the circular periphery of theheel portion of the last fits into a complementary socket in the toeportion and provides a pivot about which the last may be swung aroundthe axis 50. After the parts of the last have been separated the frontand rear portions of the last are routed out longitudinally through anarrow area 53 which extends beyond the hinge pin holes and removes thewebs 41 between the adjacent ends of the axially alined holes. The areathus routed out provides a space for the usual link or links which arepivotally mounted upon the hinge pins which are inserted in the hingepin holes.

By reason of the fact that the oppositely dis posed drills are held inaxial alinement by the templets l0 and I l and are required to drillonly approximately half through the wood of the last, diversion of thedrills by encountering portions of the wood of different hardness isavoided and parallelism of the hinge pins is insured, so that when thelast is assembled the toe and heel portions will be restored accuratelyto their normal positions and binding entirely avoided.

A modified form of the invention is shown in Figs. 6 and '7 in which thelast is placed upon the bed of the machine and the templet and clampingmechanism mainly carried by a pivotally mounted overhanging beam. Inthis construction the base 54 of the supporting and clamping mechanismis of preferably rectangular form and is provided at its rear end withsuitable guideways 55 in which the base of an abutting member 58,similar to the abutting member 4|, may be mounted and forced forwardlyby springs 5! similar to the springs 45 above described. The oppositeend of the base 54 has secured to it or mounted upon it a vertical standor standards 58. A beam 59 is pivotally mounted upon a shaft 68 in theupper end of the standard and extends longitudinally of the base 54: Thebeam 59 may be of sheet steel of channel form, as illustrated in Fig.'7, of considerably greater width than the width of the last and theflanges SI and 82 thereof each provided with a pair of integral verticalextensions 63 forming templets having holes or guideways 84 for thedrills of the respective pairs illustrated in Fig. 1. Longitudinallyextending rails 65 and 88 and reenforcing bars 81 are welded, orotherwise secured to the inner faces of the flanges 8| and 82. asillustrated in Fig. 7. A pin 98 corresponding to the Jack pin of thelasting machine and adapted to engage the thimble ii of the last ispivotally mounted upon a rod 89 the ends of which are mounted intherails65 and 88 and spacing sleeves 18 and II surrounding the rod 89 which areinterposed between the rails and pin prevent lateral movement of the pinupon the rod 69.

By reason of this pivotal connection of the jack pin 88 suflicientlongitudinal movement of the last is permitted to enable it properly tobe positioned longitudinally for the drilling of the hinge pin holes.

vMeans are provided to engage the arch portion 01' the last which asillustrated in Figs. 6 and 7 comprises converging plates 12 and 13having at their upper ends contacting integral bosses 14 which aremounted upon a rod 15 journalled at its ends in the rails 65 and 66 inthe manner above described. A suitable detachable resilient member 18adapted to fit the arch portion of the last is held between the plates12 and 13. A rod 11, which is pivotally mounted upon a rod 18 in asimilar manner, depends from the central portion of the beam 29 over thetoe portion of the last and has telescopically mounted upon it acylindrical sleeve 19 having a head 88 to engage the toe portion of thelast. The sleeve 19 is provided at its upper portion with a longitudinalslot 8| which is engaged by a pin 82 projecting from the rod 11 toprevent rotation of the sleeve relatively to the rod. A helical spring83, which is interposed between the lower end of the rod 11 and the head88 of the sleeve, serves to cause the head to engage the toe portion ofthe last with a yieldable pressure.

Suitable means are provided for vertically adjusting and clamping thetoe portion of the last. In the construction illustrated herein awedgeshaped block 84 is slidably mounted in a suitable guideway 85 inthe base and is provided with an integral forwardly extending rack 88engaged by a gear 81 fixedly secured upon a vertical shaft 88 which ismounted in the bed 54 and provided at its upper end with a knurled head89 to facilitate rotation of the shaft 88. The rack is clamped upon thebed by an offset clamping plate 99 which is secured to the bed bymachine screws.

Suitable means are provided for clamping the toe portion of the lastagainst lateral displacement. As illustrated herein clamping jaws 9i and92 are slidably mounted upon a rod 93 which passes through the block 84.These clamping jaws desirably are of substantially rectangular form withtheir fiat edges resting upon the bed plate. Screw threaded members 94and 95 mounted in opposite sides of the block 84 and having means forengaging the clamping jaws 92 provide means for adjusting the jawsfirmly against the sides of the toe portion of the last. 7

Suitable means are provided for locking the beam 59 in depressedposition. A convenient device which is illustrated herein comprises alever 96 which is mounted upon a rod 91 at the rear end of the beam 59and is provided with a handle 98 and near its pivot with a recess 89 soconstructed that when the beam is depressed and the handle forcedinwardly it will engage beneath the extension I88 of the abutment member58.

In the operation of the construction illustrated in Figs. 6, 7, and 8,the last is first placed upon the bed, the beam 58 thereupon swungdownwardly until the jack pin 68 enters the thimble I5 of the last. Thewedge-shaped support 84 for the front end of the last is then adjustedby turning the milled head 89 of the pinion 01, which actuates the rack86, in a proper direction to raise the toe portion of the lastsuificient- 1y to locate the guides 64 of the templets 63 properly withrespect to the positions of the hinge pin holes which are to be bored,the last being moved longitudinally if necessary during such adjustment.The clamping jaws 9| and 92 are then adjusted by rotating the screws 94and 95 respectively to clamp the last fixedly in position. The toeportion of the last is held down by the spring pressed head 80 of thesleeve 99. When properly positioned the lever 98 is swung downwardly toengage beneath the extension I00 oi the abutting member which yieldablyengages the heel of the last. The drilling mechanism, which is similarto that diagrammatically shown in Figs. 1 and 2, is then actuated tocause the drills to penetrate the last from opposite sides in the manneras above described and the penetration of the drills arrested before theends of the axially alined drills meet. The last is then cut and routedin the manner above described.

It will be understood that the novel method of boring hinge pin holesfor lasts above described can thus be performed either upon the machinesillustrated respectively in Figs. 1 to 5, or 6 to 8 of the drawings, orthat the method may be performed by hand by two operativessimultaneously actuating oppositely alined drills guided accurately inany suitable manner.

It will also be understood that the particular mechanisms for performingthe method are of an illustrative character and that various changes inconstruction and arrangement of parts may be made within the spirit andscope of the following claim.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

Steps in the method of making two-part lasts having hinge pins in theheel part and fore part of the last which consists first, insimultaneously drilling in the heel and fore portions respectively 15 ofan undivided last axially alined holes for both of the hinge pins frompredetermined points on opposite sides of the last approximately to thelongitudinal central plane of the last, but leaving a narrow web ofmaterial between the adjacent ends of the bores. second, cutting thelast in such manner as to form a fore part and a heel part andprovidingv for pivotal movement therebetween and third, routing therespective fore and heel portions centrally and longitudinally of thelast from the complementary abutting surfaces to provide a, hinge recesscommunicating with the bores for the hinge pins.

JOHN M. MADIGAN.

